Using the tabbox task switcher effect logs this output: kwin_x11: file:///usr/share/kwin/tabbox/present_windows/contents/ui/main.qml:89:21: QML RowLayout: Binding loop detected for property "height"
Confirmed here, on a fairly vanilla Arch Linux installed in early 2017 and updated occasionally (including recently). Been seeing this for a while. Still present with kwin 5.16.5-2 right now, as well as the originally-reported 5.12.3. (IDK when it actually started). I haven't manually edited any KDE config files. This causes major bloat in systemd log files, cluttering journalctl output when looking for other things.
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